I want to make crispy fried chicken and waffles. I have had great luck boiling chicken wings and then deep frying them. Can I do the same thing for fried chicken? Boil, brine in buttermilk mixture, coat and then fry? Or is there a better way?
Short answer: Brining after boiling won't do much (if anything), and you probably don't want to boil all parts of the chicken anyway.
One primary purpose of brining is to hydrate the cells of the muscle tissue before cooking, which allows the cells to hold on to more moisture during the cooking process via denaturation of the proteins. If you cook the meat first, then the heat will permanently denature the proteins first, so the brine will essentially be useless.
The reason why you want to pre-cook chicken wings is that (a) they have a lot of fat which melts off into the cooking liquid, and (b) they have a good amount of connective tissue (collagen) which needs to be cooked low and slow to soften into delicious gelatin. Most of the other parts of the chicken don't have nearly as much fat and collagen, so boiling them would likely only serve to overcook them.
My wife soaks her chicken in buttermilk and spices overnight. However there is no boiling involved. I'm not sure how boiling would affect the soaking process, but I'd guess not favorably. Are you just looking to reduce the frying time by boiling the chicken first? If so, maybe you could go with an "easy" fried chicken technique, where you finish in the oven.